Those who deal in social cause marketing often have the cards stacked against them. Sad as it is, non-profit efforts and public service programs often have to work harder to generate enthusiasm, particularly when compared with the flashy and inherently desirable consumer products with which they must compete. To combat this potential disadvantage, social cause marketers must find ways to distinguish and differentiate themselves. Sometimes they employ a celebrity to help draw attention to their cause. Other times, they get a little weird.

You’re bound to have seen it: a public service ad that uses an exceedingly odd concept to set itself apart. Scan long-running social advertising blog Osocio and you’ll see exactly what I mean. Promoting a Netherlands phone number citizens can use to report animal neglect or abuse, for example, is honorable. Doing it by digitally animating animals so that their bodies form the mutated shape of the digits…that’s a little unorthodox. And yet, this kind of approach isn’t uncommon. Two current campaigns running in the U.S. demonstrate a similar penchant for peculiarity.

The first, called “Wasting Water is Weird,” was created by advertising and marketing agency Shelton Group in partnership with the Environmental Protection Agency’s WaterSense program to increase awareness about water waste. It includes a website, online ads and videos, and social and outdoor media.

The campaign stars a character named Rip the Drip who loves wasting water and appears to people whenever they’re doing it, too. Besides the fact that he looks like Jim Carrey in “Dumb & Dumber” and demonstrates a desperation not unlike that of “Alan” in “The Hangover,” there’s something a little off about the guy. Everyone who meets Rip looks thoroughly freaked out.

The American Institute of Certified Public Accountants (AICPA)’s newest “Feed the Pig” PSA campaign takes a similar approach, only its creepy character is a talking, walking piggy bank named Benjamin Bankes. You may have seen Americans chasing him down in TV spots and online videos, or caught him addressing consumers on Facebook and through Twitter. The campaign, which was developed in conjunction with the Ad Council, includes the website FeedThePig.org where consumers can find tips for breaking bad habits like Takeout and Shoe Addiction and complete quizzes to help determine where else they can save.

If unnerving characters and bizarre concepts are so popular in PSAs, surely that must mean they work. Rip the Drip’s weirdness does manage to get the consumers in his ads to stop wasting water, and I’d venture to say that when coupled with common images of water waste he’s memorable enough to convince those who are watching to think twice as well. The same goes for Benjamin Bankes. As an icon he’s unforgettable, and a perfect representation of the campaign’s message of responsibility and sensible spending.

The presence of these two unusual suspects isn’t unprecedented. Who could forget the “Subservient Chicken” that launched the interactive video viral marketing craze, or the rash of Orbit Gum campaigns that included references to “dirty mouths,” “dirty words,” and even the “Friends of Bright,” a whiteness-obsessed cult? These advertising efforts succeeded in being memorable not just because they were creepy, but because they sent a message that stuck with consumers.

Unorthodox ads aren’t effective by virtue of being unorthodox, and this is the detail that trips marketers up. Often brands will get excited about the idea of doing something different and forget that, at its core, a campaign still has to deliver a clear message about the product or service it’s intended to promote. One session with the Subservient Chicken and it was ingrained in your psyche that you could go into any Burger King and have your chicken sandwich “your way.” One look at the slot in the top of Benjamin Bankes’s head and you can’t help but think, “I should really start putting a little more away.”

Does creepy work? Sure it does. But only if your brand’s creative strategy team is working, too.